Slip bowl



B. F. KELLEY Nov. 10, 1964 SLIP BOWL Filed Dec. 4, 1961 56/7 4707? F /(eHey INVENTOR. &/-k

s w v ATTORNEY United States. Patent 3,156,026 SLIP BOWL Benjamin F.Kelley, Tulsa, Okla, assignor to Ben F. Kelley Co., Inc, a corporationof Oklahoma Filed Dec. 4, 1961, Ser. No. 156,605 6 Claims. (Cl. 24-263)This invention relates to improvements in slip bowls.

Slip bowls are commonly used in well drilling to form seats forpipe-gripping slips which are employed to grip pipe strings as thelatter are inserted into and removed from well bores during the courseof drilling wells and while running pipe for equipping wells.

Such slip bowls will commonly have a downwardly tapering conical borethrough which the pipe is run to provide a seat surface for wedging theslips into gripping engagement with the pipe.

In oil well drilling operations, drill pipe, which is run through thebowl, will ordinarily be made up of sections connected together by tooljoints or other couplings which form enlargements about the surface ofthe pipe. Tool joints are frequently made of metal which is harder thanthe metal of the slip bowl. As a result, in the course of running thepipe through the bowl, the surfaces of the bowl, particularly at thethroat or smaller diameter region of the conical bore, will become badlyworn so that the slips will be deprived of full bearing surface on theslip bowl, thereby making their grip upon the pipe uncertain andfrequently hazardous. This is particularly true in the case of theso-called automatic or power slips by which the slips. are raised andlowered relative to the slip bowl by power means during gripping andreleasing of the pipe.

It is, therefore, a primary object of the present invention to providean improved slip bowl construction which will obviate the difficultiessuch as are enumerated above,

which are encountered in the use of more conventional slip bowls.

A further object is to provide a slip bowl having a removable wear ringor guide bushing positioned at the throat of the bowl where the greatestdegree of wear is normally encountered.

A further object is to provide a slip bowl employing a removable hardmetal wear ring or guide bushing in the throat of the bowl and a splitretainer ring for holding the bushing in place but which may be removedfor replacement of the bushing as the latter becomes worn in service.

Other and more specific objects of this invention will become morereadily apparent from the following detailed description when read inconjunction with the accompanying drawing which illustrates a usefulembodiment in accordance with this invention.

In the drawing:

FIG. 1 is a vertical cross-sectional view of a slip bowl constructed inaccordance with this invention;

FIG. 2 is a transverse cross-sectional view looking upwardly along line22 of FIG. 1; and

FIG. 3 is a fragmentary view, in perspective, illustrating a detail ofthe invention.

As shown in the drawing, the slip bowl, designated generally by theletter B, is shown in the position commonly occupied in a conventionalmaster bushing M seated in the usual rotary table R of a rotary welldrilling rig. The rotary table and master bushing form no part of thepresent invention and are shown in broken lines merely for purposes ofillustration of a conventional support for the slip bowl.

Slip bowl B may be of any suitable so-called solid type, that is, acontinuous structure as compared with split types which are alsocommonly used in the well drilling industry. Bowls of the solid type arecommonly used 3,156,026 Patented Nov. 10, 1964 "ice with power slips andoften in running casing as well as other types of pipe strings. As shownin the illustrative embodiment, slip bowl B comprises a body 10 which isprovided about its upper end with an annular flange F which is adaptedto rest on the top surface of master bushing M. Also, the exterior ofslip bowl B is provided immediately below flange F with a portion 12 ofsquare or other non-round shape to seat non-rotatably in a correspondingopening in master bushing M. The remainder of the exterior surface ofthe slip bowl extending below portion 12 will ordinarily have agenerally conical inwardly tapering shape, indicated at 13, for seatingin a correspondingly shaped seat provided in master bushing M.

Body 11) of the slip bowl has an axial bore comprising a main bowlportion 14 of downwardly and inwardly tapering, generally conicalshapemerging into a throat portion 15. The latter merges with a downwardlyand outwardly flaring bore portion 17, also of generally conical form.In the region of throat portion 15, the bore Wall of the slip bowl isprovided with an annular recess 18 coaxial with the bore of the bowl andgenerally cylindrical in shape. The upper end of the recess is definedby the downwardly facing shoulder 16. The lower end of recess 18 isenlarged diametnically for a short distance to form a relatively narrowannular groove 19 in the wall of the bowl, terminating just above thelower end of the bowl.

Seated in recess 18 is a wear ring or guide bushing 20 which will beconstructed of relatively hard metal or metal which has been treated toprovide a hard external surface, the metal or hardened surface beingharder than the metal from which the bowl is constructed. The bore ofbushing 20 will be coaxial with that of the slip bowl and the innerperiphery of bushing 20 is shaped to define the throat portion of thebowl. The upper portion of the bore of bushing 20 is provided with adownwardly and inwardly tapering surface 21 forming a continuation ofthe surface of bowl portion 14 and leading into a short cylindricalportion 21a. The portion 21b of the bore of bushing 20 below cylindricalportion 21a, tapers downwardly and outwardly to conform to the slope ofportion 17 of the bore of the slip bowl. A split retainer ring,designated generally by the numeral 22, is seated in groove 19 andcomprises at least four complementary arcuate segments, one of which maybe designated the key segment 22a and is preferably made considerablyshorter than the other three segments, designated 22b, 22c, and 22d. Keysegment 22a is provided with a radially outwardly projecting stud orrivet 24 which is adapted to project through a registering hole 25extending from the bottom of groove 19 through the wall of the slipbowl. The outer end of rivet 24, when the ring is in place, will projectthrough hole 25 and may be peened or otherwise riveted to secure it inplace in hole 25, thereby securing the retainer ring below bushing 20 inretaining relation to the lower end thereof. The upper end of bushing 20will be held against upward displacement by engagement with shoulder 16.The inner periphery of retainer ring 22 is formed with a conical taper26 diverging downwardly to conform with the taper of portion 17 of theslip bowl and portion 21b of the bushing.

Bushing 20 will be made to have a sliding fit in recess 18 so that whileit cannot be displaced from the recess, it is free to rotate in therecess. This is quite important because, as pipe is run through the slipbowl, the ability of the bushing to rotate freely will reduce thepossibility of excessive wear on the bushing at any particular point,and thus will tend to assure uniformity of wear over the entire surfaceof the bushing.

Whenever the wear of the bushing does become excessive, the retainerring can be removed by cutting off the expanded or riveted portion ofstud 24 and knocking segment 2211 out of groove 19, thereby allowing theother segments of the ring to be removed. Thereupon, bushing 20 can beslipped out of recess 13 and a new bushing substituted therefor and thenlocked in place by a new retainer ring.

By means of the construction previously described, it will be seen thatthe life of slip bowls can be greatly extended by the use of a hardenedreplaceable guide bushing which is positioned in the region of the bowlin which excessive wear occurs.

It will be understood that various changes and alterations may be madein the details of the illustrative embodiment within the scope of theappended claims but without departing from the spirit of this invention.

What I claim and desire to secure by Letters Patent is:

1. A slip bowl, comprising, a generally tubular metal body having agenerally conical bore tapering downwardly and inwardly from its upperend, an annular guide bushing rotatably seated wholly within the wall ofsaid bore above its lower end to define the throat portion of said bore,said bushing being constructed of metal harder. than said body, and asplit retainer ring seated in the bore wall of said body beneath thelower end of said bushing to secure the latter in place in said borewall.

2. A slip bowl according to claim 1 wherein said retainer ring comprisesa plurality of complementary arcuate segments, and wherein there aremeans carried by at least one of said segments for fixedly securing thesame to said body.

3. A slip bowl according to claim 1 wherein said retaining ringcomprises a plurality of complementary arits upper end, a coaxialannular recess in the wall of said bore above its lower end, an annulargroove in the wall of said bore communicating with the lower end of saidrecess and. larger in diameter than the latter, anannular guide bushingrotatably seated wholly within said recess, the bore of said bushingdefining the throat portion of said bowl, said bushing being constructedof metal harder than said body, and a split retainer ring seated in saidgroove in retaining relation to the lower end of said guide bushing.

5. A slip bowl according to claim 4 wherein said retainer ring comprisesa plurality of complementary arcilate segments,and wherein there aremeans carried by at least one of said segments for fixedly securing thesame to said body.

6. A slip bowl, comprising, a generally tubular metal body having athrough bore comprising a generally conical first bore portion taperingdownwardly and inwardly from its upper end merging with a generallyconical second bore portion tapering downwardly and outwardly to thelower end of the body, a coaxial annular recess in wall of said bore atthe juncture of said bore portions, an annular guide bushing constructedof metal relatively harder than said body rotatably seated wholly withinsaid recess, the upper and lower end portions of the bore wall of saidbushing having tapers respectively forming portions of said first andsecond bore portions and defining the throat portion of the slip bowl,and a split retainer ring seated in the Wall of said second bore portionin retaining relation to the lower end of said guide bushing, the innerwall of said retainer ring having a taper corresponding substantially tothat of said second bore portion, said retainer ring comprising aplurality of complementary arcuate segments, and means carried by atleast one of said segments for fixedly securing the same to said body.

References Cited in the file of this patent UNITED STATES PATENTS2,075,028 Driscoll Mar. 30, 1937 2,126,933 Stone et al Aug. 16, 19382,855,182 Payne Oct. 7, 1958 3,017,936 Long Jan. 23, 1962

1. A SLIP BOWL, COMPRISING, A GENERALLY TUBULAR METAL BODY HAVING AGENERALLY CONICAL BORE TAPERING DOWNWARDLY AND INWARDLY FROM ITS UPPEREND, AN ANNULAR GUIDE BUSHING ROTATABLY SEATED WHOLLY WITHIN THE WALL OFSAID BORE ABOVE ITS LOWER END TO DEFINE THE THROAT PORTION OF SAID BORE,SAID BUSHING BEING CONSTRUCTED OF METAL HARDER THAN SAID BODY, AND ASPLIT RETAINER RING SEATED IN THE BORE